Floor cleaning in public, commercial, institutional and industrial buildings have led to the development of various specialized floor cleaning machines, such as hard and soft floor cleaning machines. These cleaning machines generally utilize a cleaning head that includes one or more cleaning tools configured to perform the desired cleaning operation on the floor surface. These cleaning machines include dedicated floor sweeping machines, dedicated floor scrubbing machines and combination floor sweeping and scrubbing machines.
An example of a dedicated hard floor sweeping and scrubbing machine is described in U.S. Pat. No. 5,901,407, which is assigned to Tennant Company of Minneapolis, Minn. and which is hereby incorporated by reference in its entirety. The machine uses a cleaning head having two cleaning tools in the form of cylindrical brushes. The cleaning tools counter-rotate in the directions indicated by the arrows shown. Water, detergent and/or cleaning solution are sprayed on the floor ahead of the brushes so the brushes can scour the floor at the same time they are sweeping debris from the floor. A vacuum squeegee removes fluid waste from the floor during the wet scrubbing and sweeping operations. The cleaning tools engage each other such that debris on the floor is swept between the two cleaning tools and is directed into a waste hopper by a deflector.
An example of a dedicated floor sweeper is described in U.S. Pat. No. 4,571,771, which is assigned to Tennant Company of Minneapolis, Minn. and is hereby incorporated by reference in its entirety. The floor sweeper includes a cleaning head comprised of a rotating cylindrical brush that contacts the floor and throws loose debris into a hopper which is periodically emptied either manually or through a motorized lift. Combination floor sweeping and scrubbing machines were developed to avoid the necessity of having two machines. Some floor sweeping and scrubbing machines were created by mounting sweeping components to the front end of a dedicated scrubbing machine to making one large, multi-function machine.
When a surface maintenance machine performs wet scrubbing operation, water, detergent and/or cleaning solution from a solution tank are sprayed or poured on the floor through a solution valve to the brushes. As the surface maintenance machine moves forward, a squeegee wipes the waste water off the floor, and a vacuum system applies suction to remove the waste water from the floor upwards through a recovery hose and into a recovery tank. When the vacuum supply is turned off, any waste water still present in the recovery hose flows down to the floor due to lack of suction. This is referred to as hose runoff. Hose runoff is typically prevented by tying a knot or including a loop in the recovery hose.